As there is currently no default Birthdate field within the Shopify Customer record, we are unable to automatically add Shopify customer sign-ups into the Happy Birthday app.
We do, however, have an integration with Customer Fields which is a Shopify app that allows Merchants to create custom fields and forms to collect unique information about their customers when they register or edit their profile.
Our integration will push each new customer sign-up containing a birthday (you can make it a mandatory field) directly into the Happy Birthday app, adding them to your Birthday Club.
We have a number of articles covering the integration with Customer Fields here:
Customer Fields integration docs
Find out more about the Customer Fields app via their Shopify app listing here
You may also be interested in a feature we have that stores birthdays within Shopify Customer Metafields.
Need any help?
If you would like any advice or support on setting up the customer Fields integration, please don't hesitate to get in touch.